1. Field of the Invention
The present invention relates to the field of soil manipulation devices for agricultural use.
2. Description of the Background Art
There are several ways in which farm land is prepared for planting or seeding. In the past, the land was turned over by a plow, cut by disks, pulverized by a harrow, etc. However, preparing the soil in this manner is less desirable or unacceptable in some circumstances due to erosion problems caused by use of the above apparatus, particularly such use on contoured land. Thus, there has been significant interest in "low-till" and "no-till" farming, which, rather than turning over and tilling an entire field, tills only spaced strips of soil. This method of soil preparation reduces the damaging effects of erosion on the soil.
The strips of soil are tilled by tools which penetrate the surface of the soil and form a seedbed area for planting. The apparatus may use a fixed tiller point to till the soil, or rotatable coulter wheels or disks to cut and mix the soil, followed by a penetrating blade for additional cultivation of the soil. In addition, apparatus for penetrating the soil hardpan to form a passage therein beneath the seedbed may be used as well. The tillage apparatus may be followed by a planter or drill which places seed in the seedbed prepared along each strip of soil. Alternatively, the soil can be tilled in the fall to form a bed which can be seeded the following spring.
There remains a need in the art for improved apparatus for soil manipulation and preparation of seedbeds and specifically in providing an apparatus which can adapt downward coulter force to changing field conditions and also in providing an apparatus for breaking up soil hardpan while minimizing surface soil disturbance.